Existing navigation and map services plan routes based on raw map data such as street information including allowed/estimated average speeds. Although the map data is often carefully tuned, sometimes the route an experienced driver would take differs from a route proposed by a navigation system and/or the proposed route may require considerably less or more travel time. This is often an inconvenience to experienced drivers wishing to take an alternative route.
For example, this is can an inconvenience for carpool participants, where a driver may be continually matched with the same passengers for each ride and where the computed route is crucial for the pick-up and drop-off of each passenger. If the driver usually takes a different route or the route take more or less time, the navigation system time table and resulting calculations for pick-up and drop-off times may be skewed, which leads to an increased dissatisfaction for the passengers.